给图片添加水印，其实就是把原来的图片和水印添加在一起，下面小编把最近整理的资料分享给大家。

php对图片文件的操作主要是利用GD库扩展。当我们频繁利用php对图片进行操作时，会自然封装很多函数，否则会写太多重复的代码。当有很多对图片的相关函数的时候，我们可以考虑将这些函数也整理一下，因而就有了封装成类的想法。

操作图片主要历经四个步骤：

第一步：打开图片

第二步：操作图片

第三步：输出图片

第四步：销毁图片

1,3,4三个步骤每次都要写，每次又都差不多。真正需要变通的只有操作图片的这一步骤了。操作图片又往往通过1或多个主要的GD函数来完成。

本文封装类里面的四种方法，文字水印（imagettftext()），图片水印（imagecopymerge()），图片压缩，图片剪切(imagecopyresampled())，其余的常用GD函数便不赘述。

直接上代码：

<?php

class Image

{

private $info;

private $image;

public $type;

public function __construct($src)

{

$this->info=getimagesize($src);

$this->type=image_type_to_extension($this->info['2'],false);

$fun="imagecreatefrom{$this->type}";

$this->image=$fun($src);

}

/**

* 文字水印

* @param [type] $font 字体

* @param [type] $content 内容

* @param [type] $size 文字大小

* @param [type] $col 文字颜色（四元数组）

* @param array $location 位置

* @param integer $angle 倾斜角度

* @return [type]

*/

public function fontMark($font,$content,$size,$col,$location,$angle=0){

$col=imagecolorallocatealpha($this->image, $col['0'], $col['1'], $col['2'],$col['3']);

imagettftext($this->image, $size, $angle, $location['0'], $location['1'], $col,$font,$content);

}

/**

* 图片水印

* @param [type] $imageMark 水印图片地址

* @param [type] $dst 水印图片在原图片中的位置

* @param [type] $pct 透明度

* @return [type]

*/

public function imageMark($imageMark,$dst,$pct){

$info2=getimagesize($imageMark);

$type=image_type_to_extension($info2['2'],false);

$func2="imagecreatefrom".$type;

$water=$func2($imageMark);

imagecopymerge($this->image, $water, $dst[0], $dst[1], 0, 0, $info2['0'], $info2['1'], $pct);

imagedestroy($water);

}

/**

* 压缩图片

* @param [type] $thumbSize 压缩图片大小

* @return [type] [description]

*/

public function thumb($thumbSize){

$imageThumb=imagecreatetruecolor($thumbSize[0], $thumbSize[1]);

imagecopyresampled($imageThumb, $this->image, 0, 0, 0, 0, $thumbSize[0], $thumbSize[1], $this->info['0'], $this->info['1']);

imagedestroy($this->image);

$this->image=$imageThumb;

}

/**

* 裁剪图片

* @param [type] $cutSize 裁剪大小

* @param [type] $location 裁剪位置

* @return [type] [description]

*/

public function cut($cutSize,$location){

$imageCut=imagecreatetruecolor($cutSize[0],$cutSize[1]);

imagecopyresampled($imageCut, $this->image, 0, 0, $location[0], $location[1],$cutSize[0],$cutSize[1],$cutSize[0],$cutSize[1]);

imagedestroy($this->image);

$this->image=$imageCut;

}

/**

* 展现图片

* @return [type] [description]

*/

public function show(){

header("content-type:".$this->info['mime']);

$funn="image".$this->type;

$funn($this->image);

}

/**

* 保存图片

* @param [type] $newname 新图片名

* @return [type] [description]

*/

public function save($newname){

header("content-type:".$this->info['mime']);

$funn="image".$this->type;

$funn($this->image,$newname.'.'.$this->type);

}

public function __destruct(){

imagedestroy($this->image);

}

}

?>

如果还需要其他操作，只需要再往这个类里面添加就好啦~~

给图片添加水印代码：

先看文件check_image_addwatermark.php代码

<?php

//修改图片效果

$db = mysql_connect('localhost','root','Ctrip07185419') or die('can not connect to database');

mysql_select_db('moviesite',$db) or die(mysql_error($db));

//上传文件的路径

$dir = 'D:Seriousphpdevtestimages';

//设置环境变量

putenv('GDFONTPATH='.'C:WindowsFonts');

$font = "arial";

//upload_image.php页面传递过来的参数，如果是上传图片

if($_POST['submit'] == 'Upload')

{

if($_FILES['uploadfile']['error'] != UPLOAD_ERR_OK)

{

switch($_FILES['uploadfile']['error'])

{

case UPLOAD_ERR_INI_SIZE:

die('The uploaded file exceeds the upload_max_filesize directive');

break;

case UPLOAD_ERR_FORM_SIZE:

die('The upload file exceeds the MAX_FILE_SIZE directive that was specified in the HTML form');

break;

case UPLOAD_ERR_PARTIAL:

die('The uploaded file was only partially uploaded');

break;

case UPLOAD_ERR_NO_FILE:

die('No file was uploaded');

break;

case UPLOAD_ERR_NO_TMP_DIR:

die('The server is missing a temporary folder');

break;

case UPLOAD_ERR_CANT_WRITE:

die('The server fail to write the uploaded file to the disk');

break;

case UPLOAD_ERR_EXTENSION:

die('The upload stopped by extension');

break;

}

}

$image_caption = $_POST['caption'];

$image_username = $_POST['username'];

$image_date = date('Y-m-d');

list($width,$height,$type,$attr) = getimagesize($_FILES['uploadfile']['tmp_name']);

$error = 'The file you upload is not a supported filetype';

switch($type)

{

case IMAGETYPE_GIF:

$image = imagecreatefromgif($_FILES['uploadfile']['tmp_name']) or die($error);

break;

case IMAGETYPE_JPEG:

$image = imagecreatefromjpeg($_FILES['uploadfile']['tmp_name']) or die($error);

break;

case IMAGETYPE_PNG:

$image = imagecreatefrompng($_FILES['uploadfile']['tmp_name']) or die($error);

break;

default:

break;

}

$query = 'insert into images(image_caption,image_username,image_date) values("'.$image_caption.'" , "'.$image_username.'","'.$image_date.'")';

$result = mysql_query($query,$db) or die(mysql_error($db));

$last_id = mysql_insert_id();

// $imagename = $last_id.'.jpg';

// imagejpeg($image,$dir.'/'.$imagename);

// imagedestroy($image);

$image_id = $last_id;

imagejpeg($image , $dir.'/'.$image_id.'.jpg');

imagedestroy($image);

}

else //如果图片已经上传，则从数据库中取图片名字

{

$query = 'select image_id,image_caption,image_username,image_date from images where image_id='.$_POST['id'];

$result = mysql_query($query,$db) or die(mysql_error($db));

extract(mysql_fetch_assoc($result));

list($width,$height,$type,$attr) = getimagesize($dir.'/'.$image_id.'.jpg');

}

//如果是保存图片

if($_POST['submit'] == 'Save')

{

if(isset($_POST['id']) && ctype_digit($_POST['id']) && file_exists($dir.'/'.$_POST['id'].'.jpg'))

{

$image = imagecreatefromjpeg($dir.'/'.$_POST['id'].'.jpg');

}

else

{

die('invalid image specified');

}

$effect = (isset($_POST['effect'])) ? $_POST['effect'] : -1;

switch($effect)

{

case IMG_FILTER_NEGATE:

imagefilter($image , IMG_FILTER_NEGATE); //将图像中所有颜色反转

break;

case IMG_FILTER_GRAYSCALE:

imagefilter($image , IMG_FILTER_GRAYSCALE); //将图像转换为灰度的

break;

case IMG_FILTER_EMBOSS:

imagefilter($image , IMG_FILTER_EMBOSS); //使图像浮雕化

break;

case IMG_FILTER_GAUSSIAN_BLUR:

imagefilter($image , IMG_FILTER_GAUSSIAN_BLUR); //用高斯算法模糊图像

break;

}

if(isset($_POST['emb_caption']))

{

imagettftext($image , 12 , 0 , 20 , 20 , 0 , $font , $image_caption);

}

if(isset($_POST['emb_logo']))

{

//获取水印图片的尺寸并创建水印

list($wmk_width , $wmk_height) = getimagesize('images/logo.png');

$x = ($width-$wmk_width) / 2;

$y = ($height-$wmk_height)/2;

$wmk = imagecreatefrompng('images/logo.png');

//把水印图片和原图片合并在一起

imagecopymerge($image , $wmk , $x , $y , 0 , 0 , $wmk_width , $wmk_height , 20);

//清除水印图片

imagedestroy($wmk);

}

imagejpeg($image , $dir.'/'.$_POST['id'].'.jpg' , 100);

?>

<html>

<head>

<title>Here is your pic!</title>

</head>

<body>

<h1>Your image has been saved!</h1>

<img src="images/<?php echo $_POST['id'];?>.jpg" alt="" />

</body>

</html>

<?php

}

else

{

?>

<html>

<head>

<title>Here is your pic!</title>

</head>

<body>

<h1>So how does it feel to be famous?</h1>

<p>Here is the picture you just uploaded to your servers:</p>

<!--<img src="images/<?php echo $imagename;?>" alt="" style="float:left;" />-->

</body>

</html>

<?php

if($_POST['submit'] == 'Upload')

{

$imagename = 'images/'.$image_id.'.jpg';

}

else

{

$imagename = 'image_effect.php?id='.$image_id.'&e='.$_POST['effect'];

if(isset($_POST['emb_caption']))

{

$imagename .= '&capt='.urlencode($image_caption);

}

if(isset($_POST['emb_logo']))

{

$imagename .= '&logo=1';

}

}

?>

<img src="<?php echo $imagename;?>" style="float:left;" alt="" />

<table>

<tr>

<td>Image save as:</td>

<td><?php $image_id?></td>

</tr>

<tr>

<td>Height:</td>

<td><?php echo $height;?></td>

</tr>

<tr>

<td>Widht:</td>

<td><?php echo $width;?></td>

</tr>

<tr>

<td>Upload date:</td>

<td><?php echo $image_date;?></td>

</tr>

</table>

<p>You may apply a special effect to your image from the list of option below.

Note:saving an image with any of the filters applied <em>can be undone</em>

</p>

<form action="<?php echo $_SERVER['PHP_SELF'];?>" method="post">

<div>

<input type="hidden" name="id" value="<?php echo $image_id;?>"/>

Filter:<select name="effect" id="">

<option value="-1">None</option>

<?php

echo '<option value="'.IMG_FILTER_GRAYSCALE.'" ';

if(isset($_POST['effect']) && $_POST['effect'] == IMG_FILTER_GRAYSCALE)

{

echo 'selected="selected"';

}

echo ' >Black and white</option>';

echo '<option value="'.IMG_FILTER_GAUSSIAN_BLUR.'"';

if(isset($_POST['effect']) && $_POST['effect'] == IMG_FILTER_GAUSSIAN_BLUR)

{

echo ' selected="selected"';

}

echo '>Blur</option>';

echo '<option value="'.IMG_FILTER_EMBOSS.'"';

if(isset($_POST['effect']) && $_POST['effect'] == IMG_FILTER_EMBOSS)

{

echo 'selected="selected"';

}

echo '>Emboss</option>';

echo '<option value="'.IMG_FILTER_NEGATE.'"';

if(isset($_POST['effect']) && $_POST['effect'] == IMG_FILTER_NEGATE)

{

echo 'selected="selected"';

}

echo '>Negative</option>';

?>

</select><br />

<?php

echo '<input type="checkbox" name="emb_caption"';

if(isset($_POST['emb_caption']))

{

echo ' checked="checked"';

}

echo ' />Embed caption in image?';

echo '<br />';

//添加水印选项

echo '<input type="checkbox" name="emb_logo" ';

if(isset($_POST['emb_logo']))

{

echo 'checked="checked"';

}

echo ' />Embed watermarked logo in image?';

?>

<input type="submit" value="Preview" name="submit" /><br /><br />

<input type="submit" value="Save" name="submit" />

</div>

</form>

<?php

}

?>

这里面主要是添加水印选项，如果选中添加水印则将logo.png作为水印图片和原来的图片合并在一起。

在预览文件中添加了对应的逻辑，代码如下：

<?php

$dir = 'D:Seriousphpdevtestimages';

//设置环境变量

putenv('GDFONTPATH='.'C:WindowsFonts');

$font = "arial";

if(isset($_GET['id']) && ctype_digit($_GET['id']) && file_exists($dir.'/'.$_GET['id'].'.jpg'))

{

$image = imagecreatefromjpeg($dir.'/'.$_GET['id'].'.jpg');

}

else

{

die('invalid image specified');

}

$effect = (isset($_GET['e'])) ? $_GET['e'] : -1;

switch($effect)

{

case IMG_FILTER_NEGATE:

imagefilter($image , IMG_FILTER_NEGATE);

break;

case IMG_FILTER_GRAYSCALE:

imagefilter($image , IMG_FILTER_GRAYSCALE);

break;

case IMG_FILTER_EMBOSS:

imagefilter($image , IMG_FILTER_EMBOSS);

break;

case IMG_FILTER_GAUSSIAN_BLUR:

imagefilter($image , IMG_FILTER_GAUSSIAN_BLUR);

break;

}

if(isset($_GET['capt']))

{

//echo $_GET['capt'];

imagettftext($image, 12, 0, 20, 20, 0, $font, $_GET['capt']);

}

if(isset($_GET['logo']))

{

list($widht , $height) = getimagesize($dir.'/'.$_GET['id'].'.jpg');

list($wmk_width , $wmk_height) = getimagesize('images/logo.png');

$x = ($widht-$wmk_width) / 2;

$y = ($height-$wmk_height) / 2;

$wmk = imagecreatefrompng('images/logo.png');

imagecopymerge($image , $wmk , $x , $y , 0 , 0 , $wmk_width , $wmk_height , 20);

imagedestroy($wmk);

}

header('Content-Type:image/jpeg');

imagejpeg($image , '' , 100);

?>

最后上传的水印图片效果如下：

注意主要的逻辑就是通过 imagecopymerge() 方法把两个图片合并在一起造成水印效果。来看看这个方法的方法原型和参数：

bool imagecopymerge ( resource $dst_im , resource $src_im , int $dst_x , int $dst_y , int$src_x , int $src_y , int $src_w , int $src_h , int $pct )

将 src_im 图像中坐标从 src_x，src_y 开始，宽度为 src_w，高度为 src_h 的一部分拷贝到 dst_im 图像中坐标为 dst_x 和 dst_y 的位置上。两图像将根据 pct 来决定合并程度，其值范围从 0 到 100。当 pct = 0 时，实际上什么也没做，当为 100 时对于调色板图像本函数和 imagecopy() 完全一样，它对真彩色图像实现了 alpha 透明。
以上内容是本文介绍PHP给图片添加水印 压缩 剪切的封装类的全部内容，希望大家对本文介绍感兴趣。